Automatic stop mechanism for phonographs.



A. NIELSEN.

AUTOMATIC STOP MECHANISM FDR PHO NOGRAPHS.

APPucmoN mm nov.21.191s.

1,222,974. Patunted Apr. 17, 1917.

a 1 (fl/Worm UNITED sTATEs PATENT OFFICE.

AAGT] NIELSEN, OF NEW YORK, N. 'Y ASSIGNOB T0 WILLIAIVI A. CONDON. OF SUMMIT.

NEW JERSEY.

. AUTOMATIC STOP MECHANISM FOR PHONC GBAPHS.

Specification of Letters Patent.

1 atcntecl Apr. 17, 1917.

Application filed November 21, 1913. Serial No. 8H2,199.

To all whom it may concern:

Be it known that I, Ami: XIELsEN, a citizen of the Danish Monarchy. and a resident of the city, county, and State of X w York. have invented certain new and useful linprovements'in Automatic Stop Mechanisms for Phonographs, of which the following is a specification.

This invention relates to automatic stop mechanism for phonographs. The ob ect of the invention is to provide a simple and inexpensive 'mechanically operated brake mechanism for the record turntable so designed. that it will automatically brake the turntable upon the cessation of the sound and so'marranged and constructed that no adjustment or setting thereof is necessary for each record. In other words, this invention. contemplates a brake mechanism which. will automatically .brake the turntable irrespective of the length of the record and without requiring any other attention from the operator than the releasing of-the brake when a new record is to be played. Other objects will appear as this specification proceeds.

The invention is embodied in a brake mechanism comprising such elements, combinations and arrangements of parts asare hereinafter described and as are illustrated in the drawings in which- Figure 1 is aplan view of a brake mechanism embodying my invention and 'showing the same attached to a phonograph with the parts in. osition at the beginning of the laying'o a record. Parts are broken away or the sake of 'clearness and other well known parts are omitted.

Fig. 2 is a similar view showing-.anintermediate position of the tone arm, and the brake mechanism in a corresponding position.

Fig. 3 is a fragmentar 'view. showing the parts in the position of rakin Fig. 4 is a detail side view o parts of the 'brake" mechanism looking from the right in Fig. 1, and a Fig. 5 is a detail view of an attachment and i In the drawings the reference numeral 6 represents the cover of the casing of a phonograph". 7 is the turntable shaft driven by the usual spring motor (not shown). 8 is a the tone arm carrying the sound box 9 and ctiondevioe secured 'to the tone arm. 7

the stylus 10. 1.1 represents a record (arried by the turntable 12. The lunkc'mrclnlhowever. the turntable is indicated by a dot and dash line. w .iile the brake mechanism is shown in full lines.

The brake itself is preferably a friction brake and in the form of a coiled spring 13 adapted to take against the edge of the turntable. It is pivoted at 14 and provided with a handle 15 for setting it by the operator. A spring-16 urges ihe brake in the direction of rotation of the turntable when thebrakc is released. The [rake is held inactive by a tripping lever 12' which engages the brake arm 18 as shown in Figs. 1 and 2, for which purpose th tripping lever is provided with a. catch 19, see Fig. 3. 20 is a stop for the brake. arm.

The tripping lever is pivoted at '21 and' is provided with a cam :22 and a spring 23 which tends to force the catch 19 into enagement with the brake arm to. hold the rake inactive. Controlling means are provided for controlling the operation of the brake at the proper time. and, the tripping lever 17 presents merely one form of a connecting means between the controlling means with two arms 2 T and 28. the latterof which is adapted to strike the tripping lever cam 22 to operate the tripping lever, whereby to release the brake. The arm- 27 carries a downwardly projecting cam 29. 30. 30 are stops limiting the oscillations of the controlling leverjZi which is oscillated to the left by a lug 34 on a pu .ley 31 pivoted on a stud. and

- which is driven from a pulley 32 on the turntable shaft 7 by means of a belt or cord 33.

When the 111;; 34 during the rotation of the pulley 31 st ikes the arm '28, the lever 2i is-moved slightl v to the left. see Fig. The lever 2* is moved to the right by a bifurcated lever 35-. The fork 36 of the lever engages the 111 .26 and when the fork is moved to the left, he arm 2* is moved to the right.

as follows. see Fig. 5.

The lever 35 is secured to the tone arm 8 37 is a ring which may be clamped to the tone arm 8 by a screw, 38. A post 39 is-secured to the rin-gand carries afixedv disk-3&0. The lever 35 is pivoted on the post '39-and a spring or other friction device 41 keeps the lever 35 in frictional engagement with the disk 40. When the tonearm 8 moves. the lever '35 moves with itunless the lever meets an obstruction in which case the lever 35 will move with relation to" the tone arm.

The-tripping lever 17. the pulley 31 and the cont-rolling lever Q-Las we 1 as the stops may all be mounted on a base 42 for convenience in attaching the brake tothe phonograph. Only Fig. -l shows this base. p In operation a record 11 is laid upon the turntable, the stylus 10 'is set in the record groove at the beginning thereof, the brake is brought into inactive position and the turntable isthen rotated by the motor as usual. It will then be seen that during the inward swinging of the tone arm 8, the fork 36 of the lever is also-moved lnward and consequently the controlling lever Ql is moved to the right which brings the arm 28 into the path of the lug 3-1 as the latter rotates and also brings the arm 27 outof the path of the' lug 351 as seen in Fig. 1. Buteverv time the ln iii strikes the arm 28,

F1 "2, the contro ling lever 24 is again to the left and the forked lever 35 is moted to the right o1" outwardly on the tone arm 8 which is tion device 41.

possible because of the tric- -.From this'i't will beclear that so longas the tone arm 8 keeps swinging inwardly, the controlling lever 2-1 is kept oscillating-by the forked lever 35 and the lug 34, andth'at duringthis movement the lug 34 never strikes the cam 29. W'hen, however, the tone armceases to move, which occurs when the last sound of the record has been reproduced, the controlling lever 24 will no longer be I moved to the right by'the forked lever 35,

but will'remain in itsileftward position caused by the lug 34, Fig. 2. Consequently.

on the following rotation, the lug 3% will strike the cam 29 as shown in .Fig. 3, and the, controlling, lever "24 willbe moved still farther to the left and its arm '28 will strike the cam 22 on the tripping. lever to trip the latter, which relea'sesthe brake which then engages and stops the turntableas explained above. v The parts are prefer-ably so; arranged that the h1g3 contacts with the-arm 28 while thetu-rntable makes one revolution to guard against irregular or incomplete oscillations of the fork '36. which in many machines swings or oscillates slightly due to-imper- 'fect or unsteady movement of the tone arm.

Such imperfect or unsteady movements of the .tone'arm. which take the form of slight but continuous oscillations. are caused by the fact that in manufacturingrecords and talking machines it is practically impossible to make the records so mathematically perfeet that the center'thereof will accurately coincide with the center of the turntable shaft 7. Again, the central opening in the record is necessarily slightly larger than the diameter oi the turntable shaft and in placing'the record on the turntable. the record is almost always placed slight-1v ccentric to the turntable shaft.

It follows. that the movement Of-tl tone arm toward the center of the record or theturntable shaft, is not even, but isuneven, and I have observed that the tone arm may oscillate as much as three-thirty seconds of.

one inch, and this peculiarity in the 'workoperating'lever 35 for thesame reason must be movably supported-on the tone arm, because i f rigidly connected to the tone arm, the oscillatory movements of the-latter will be communicated to the lever '35, hence .to the member 24 and the latter would not operate in response to the regular move ments only of the tone arm.

The arm 28 is made long enough so that the lug 34 will contact therewith for nearly ,a complete revolution of theturntable. If

this wasnot done, the lug 3twould operate the control member 2-; prematurely and the result would be that lug 3l might strike lug 29 and trip the brake before the record had been com leted. Y

Therea ter. the tone'arm is moved out ofthe way, the record ,is removed, a new record laidon the turntable andthe brake released chine is ready to play a new record 1 by the operator by turning it-to the right hen the tone arm is'brought "into start ing-posit'ion, the lever 35 is of course also moved outwardly. .Ihis "movement would I cause'the lever 21 to be moved to the left; so

that the lug 3.& during its first rotation would strike the cam :29and the brake would be applied. To prevent this there is provided a spring 50 so posltioned that at the start the lever 35 is kept-to the left to hold the cam 29 out of the way of the-lug 3* as shown in Fig. 1 and'until afewgrooves on the record has been reproduced.

Itwill be seen that the brake willbe ap plied almostimmediately after the record has been reproduced, because at the most,

one rotation of the lug 34 can occur before it strikes the cam 29. It will further be ap- I controlling means,

parent that the brake will act irrespective of the len h of the record and that no adjusting 0 the brake mechanism, according to the length of the record. is necessaryas is the movement of the other member (in this instance the turntable acting through the rotating lug 34) to actuate the tripping lever which releases the brake.

The brake mechanism as described is very inexpensive to manufacture because nearly all the pieces can be stamped out and only a few screws are necessary toattach it to the machine.

Details in the construction may of course be varied within the scope of the claim.

I claim The combinatic n with a swinging member and a rotating I11 im ber, a brake for the latter, a brake tripping lever for normally keeping said brike in inactive position, means for actuatng said tripping ever to release the brake when" said swinging member ceases to mo 'e, said means comprising a brake controllin g lever, an arm on the latter adapted to engage said tripping lever,

an element frictionally mounted on said swinging member and in contact with said brake controlling lever for moving the same in one certain direction, a rotatmg cam driven by said r01 ating member for moving 7 said brake control ling lever in the opposite direction and for moving the said arm into direct engagement with said tripping lever to release the said brake to brake the said rotating member v 'hen the swinging member ceases to move.

Signed at New York, N. Y. this 15th day of Nov. 1913.

IELSEN. Witnesses:

, IVAN KONIG BBERG,

K. G; LE Ail). 

